1. Field of the Disclosure
This disclosure relates generally to the automatic control of hand-held dental instruments based on tip identification and controlling corresponding operating characteristics such as power control and fluid flow rate in response to particular conditions.
2. Background Description
An operator may use a powered hand-held instrument to deliver dental services to a patient. This hand-held dental delivery device may be powered by electricity or some other energy source. Examples of such dental devices include ultrasonic scalers, power polishers, and instruments for providing abrasion.
Hand-held dental delivery devices have evolved over the past decades. New techniques have been developed to expand and utilize the power and functionality of dental services, thus necessitating development of new generator circuitry, new insertable tip types and shapes, and new frequencies. This evolution has led to more complexity for operators. In addition to the functional knowledge of each different tip type, an operator must also be knowledgeable about controlling operating characteristics for each different tip during a dental procedure to create optimum procedural conditions and provide a safe environment. Examples of these operating characteristics include the energy or power level delivered to the device and the rate of fluid flow to the hand-held dental device.
Typically, an operator may control the power delivered to these hand-held devices by using an operator control input mechanism such as a switch, button, or foot pedal. The operator is enabled, via an operator control input mechanism, to adjust the power level during a dental procedure. For example, while using an ultrasonic scaler tip, a stubborn piece of tartar may require the operator to increase the power to the device in order to successfully remove it. Or, a more sensitive tooth area may warrant the operator to decrease the power delivered to a polisher.
A safe energy or power level for each tip must be maintained by the operator. For instance, the optimum safe power range (minimum and maximum energy level sent to the handpiece) of an extremely thin tip is much smaller than the safe power range of a very thick tip. If the handpiece of the dental device is driven at a level to induce maximum movement of the thickest tip type and an extremely thin tip type is placed into the handpiece, the maximum safe power of the extremely thin tip type would be exceeded. The extremely thin tip type may fatigue more rapidly and break. The tip may be rendered useless before its expected lifetime and may create a hazardous situation for the patient and the operator. Some tip types may also result in excessive vibration at unsafe power levels that may cause patient discomfort or make control of the tip difficult for the operator.
In addition to power level control, the operator must also pay attention to proper fluid flow rate for each type of dental delivery device. Fluids such as gas or liquid may be required during powered instrumentation use. For instance, while using a band-held dental device during ultrasonic scaling, water may be used as a coolant to dissipate heat that builds up in the handpiece of the dental delivery device. Liquids may act as a lubricant as well as a spot coolant at the tooth surface. They may also act as a flushing agent to remove debris from the cleaning site or as a medicament delivery system. A gas such as air may be used to dry or to clean a tooth site. Nitrous oxide may be used to provide anaesthetic relief to the patient during a dental procedure.
Fluid delivery through a hand-held powered dental delivery device may be controlled by a solenoid and a manual metering valve or regulator. The solenoid may control the on/off action of the fluid flow, and the metering valve/regulator may control the flow rate. Typically, the solenoid may be controlled by a foot pedal switch, and the flow rate may be manually controlled by a valve mounted on the unit, remotely on the dental cart or chair, or integrated into the handpiece. The operator thus may be required to use his/her hands to make adjustments to fluid delivery in addition to using the dental delivery device during the dental procedure. For instance, if a dental device requires more power to scale a stubborn piece of tartar, heat may be built up in the dental device and at the tooth site, thus requiring the operator to manually increase the flow of water for cooling. The operator may then use his/her fingers to adjust the valve to decrease the amount of water after the piece of tartar has been removed. In another example, the operator may need to manually increase the flow of a medicament while the hand-held dental device is in proximity to the site of intended application of the medicament, and decrease the flow as the instrument moves away from the site.
The evolution of hand-held dental delivery devices requires increased operator vigilance and attention to different tips, their associated characteristics and the adjustment of corresponding operating characteristics such as power levels and fluid flow rate. This forces the operator to break focus during a dental procedure, thus contributing to operator fatigue. Manual control may be cumbersome. Operator mistakes may result in premature fatigue or breakage of the dental device tip. Potential contamination of the dental site is possible through the operator's hands and fingers since s/he needs to manipulate controls throughout the procedure. A way of automatically controlling operating characteristics to a hand-held dental delivery device based on tip is needed to address these shortcomings.